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Driving factors behind multiple populations

Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 172-181页

作者： Ruoyun Huang baitian Tang Chengyuan Li Doug geisler Mario Mateo Ying-Yi Song Holger baumgardt Julio A.Carballo-bello Yue Wang Jundan Nie bruno Dias JoséG.Fernández-Trincado School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the Guangdong-Hong Kong-Macao Greater bay Area Zhuhai 519082China Departamento de Astronomía Universidad de ConcepcionConcepcionChile Instituto de Investigación Multidisciplinario en Ciencia y Tecnología Universidad de La SerenaLa SerenaChile Departamento de Astronomía Facultad de CienciasUniversidad de La SerenaChile Department of Astronomy University of MichiganAnn Arbor 48109USA David A.Dunlap Department of Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada Dunlap Institute for Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada School of Mathematics and Physics The University of QueenslandSt.Lucia QLD 4072Australia Instituto de Alta Investigación Universidad de TarapacáAricaChile CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Instituto de Astrofísica Departamento de Ciencias FísicasFacultad de Ciencias ExactasUniversidad Andres BelloSantiagoChile Instituto de Astronomía Universidad Católica del NorteAntofagastaChile

Star clusters were historically considered simple stellar populations,with all stars sharing the same age and initial chemical ***,the presence of chemical anomalies in globular clusters(GCs),called multiple stellar populations(MPs),has challenged star formation theories in dense *** studies show that mass,metallicity,and age are likely controlling parameters for the manifestation of *** the limit between clusters with/without MPs in physical parameter space is crucial to reveal the driving mechanism behind their *** this study,we look for MP signals in Whiting 1,which is traditionally considered a young *** the Magellan telescope,we obtained low-resolution spectra withinλλ=3850-5500?for eight giants of Whiting *** measured the C and N abundances from the CN and CH spectral indices.C and N abundances have variations comparable with their measurement errors(~0.1 dex),suggesting that MPs are absent from Whiting *** these findings with literature studies,we propose a limit in the metallicity *** compactness index parameter space,which relatively clearly separates star clusters with/without MPs(GCs/open clusters).This limit is physically *** a larger scale,the galactic environment determines cluster compactness and metallicity,leading to metal-rich,diffuse,old clusters formed ex *** proposed limit also impacts our understanding of the formation of the Sagittarius dwarf galaxy:star clusters formed after the first starburst(age≤8-10 Gyr).These clusters are simple stellar populations because the enriched galactic environment is no longer suitable for MP formation.

关键词： stellar galactic galaxy

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血氧水平依赖性MRI可检测急性卒中患者高危组织的代谢性状

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世界核心医学期刊文摘(神经病学分册) 2006年第12期 42-43页

作者： geisler b.S. brandhoff F. Fiehler J. 郭俊 Dr.Department of Neuroradiology University Medical Center Hamburg-EppendorfMartinistrasse 5220246 HamburgGermany

bACKGROUND AND PURPOSE-The delineation of the “penumbra”is of particular interest in acute stroke *** “mismatch concept”applying perfusion-weighted imaging(PWI)and diffusion-weighted imaging(DWI)appears to be an oversimplification of the underlying electrophysiological tissue *** additional parameter reflecting the metabolic state of the threatened brain tissue would improve our ability to describe the *** candidate is deoxyhemoglobin(deoxy-Hb)as an indicator of the oxygen extraction fraction that can be visualized by T2*-based blood oxygen level-dependent(bOLD)***-We analyzed data from 32 patients with acute stroke in the territory of the middle cerebral *** included fluid-attenuated inversion recovery,DWI,PWI,time-of-flight angiography,and quantitative T2 and T2*.(qT2,qT2*)***-up was performed on day 1 and days 5 to *** calculated 1/T2'=1/qT2*-1/*** of T2',representing the deoxy-Hb effect,were analyzed by 3D regions of interest(ROIs):apparent diffusion coefficient lesion day 0(L0),time-to-peak-lesion day 0(T0),final infarct size days 5 to 8(F5-8),lesion growth(LG;F5-8-L0),and surviving tissue(ST;T0-F5-8).RESULTS-We observed a clear decrease of T2'in the infarcted hemisphere compared with the unaffected control *** mean value showed the most pronounced loss of T2'signal intensity in L0(-15.7%),followed by LG(-10.5%)and ST(-8.0%).CONCLUSIONS-The implementation of bOLD imaging in acute stroke MRI offers a noninvasive estimation of the O2 utilization and is able to add additional information concerning the present metabolic state of the threatened brain *** changes in T2'intensity are visually noticeable in the reconstructed T2'images and provide a better estimation of the real penumbra.

关键词：急性卒中 MRI 半影区患者血氧

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用血氧水平依赖MRI对急性脑卒中患者行视觉评估的试验性研究

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放射学实践 2007年第5期22卷 526-526页

作者： Fiehler J geisler b Siemonsen S 王娟华中科技大学同济医学院附属同济医院

目的：脑卒中缺血半暗带的界定在影像学上尚存争议，本研究利于血氧水平依赖（bOLD）成像探讨缺血半暗带的代谢特征。方法：对20例脑卒中患者行MRI检查，对起病后6h内及5～8天的MRI数据进行分析。扫描序列包括DWI、T2WI、T2^＊WI，后处... 详细信息

目的：脑卒中缺血半暗带的界定在影像学上尚存争议，本研究利于血氧水平依赖（bOLD）成像探讨缺血半暗带的代谢特征。方法：对20例脑卒中患者行MRI检查，对起病后6h内及5～8天的MRI数据进行分析。扫描序列包括DWI、T2WI、T2^＊WI，后处理重建bOLD图像。采用双盲法由2位观察者对bOLD结果进行分析。结果：两位观察者正确判定病变侧的例数各占病例总数的80％和50％，

关键词：血氧水平依赖脑卒中患者 MRI检查试验性研究视觉评估缺血半暗带急性 bOLD

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Costs and cost-effectiveness of HIV early infant diagnosis in low- and middle-income countries: a scoping review

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Infectious Diseases of Poverty 2022年第4期11卷 9-28页

作者： Kira Elsbernd Karl MFEmmert-Fees Amanda Erbe Veronica Ottobrino Arne Kroid Till barnighausen benjamin P geisler Stefan Kohler Division of Infectious Diseases and Tropical Medicine Faculty of MedicineLudwig Maximilians UniversityMunichGermany Institute for Medical Information Processing Biometryand Epidemiology(IBE)Faculty of Medicine Ludwig Maximilian UniversityMunichGermany Department of Sports and Health Sciences Technical University of MunichMunichGermany Institute of Health Economics and Health Care Management Helmholtz Zentrum MunchenMunichGermany Heidelberg Institute of Global Health Heidelberg UniversityHeidelbergGermany Department of Health Management and Health Economics University of OsloOsloNorway German Center for Infection Research(DZiF) Partner SiteMunichGermany Massachusetts General Hospital/Harvard Medical School BostonMAUSA Institute of Social Medicine Epidemiology and HealthEconomicsCharite-Universitatsmedizin BerlinBerlinGermany

background:Continuing progress in the global pediatric human immunodeficiency virus(HIV)response depends on timely identification and care of infants with *** countries scale-out improvements to HIV early infant diagnosis(EID),economic evaluations are needed to inform program design and *** scoping review aimed to summarize the available evidence and discuss practical implications of cost and cost-effectiveness analyses of HIV ***:We systematically searched bibliographic databases(Embase,MEDLINE and EconLit)and grey literature for economic analyses of HIV EID in low-and middle-income countries published between January 2008 and June *** extracted data on unit costs,cost savings,and incremental cost-effectiveness ratios as well as outcomes related to health and the HIV EID care process and summarized results in narrative and tabular *** converted unit costs to 2021 USD for easier comparison of costs across ***:After title and abstract screening of 1278 records and full-text review of 99 records,we included 29 studies:17 cost analyses and 12 model-based cost-effectiveness *** costs were 21.46-51.80 USD for point-of-care EID tests and 16.21-42.73 USD for laboratory-based EID *** cost-effectiveness analyses stated at least one of the interventions evaluated to be *** studies reported costs of EID testing strategies;however,few studies assessed the same intervention or reported costs in the same way,making comparison of costs across studies *** data availability of context-appropriate costs and outcomes of children with HIV as well as structural heterogeneity of cost-effectiveness modelling studies limits generalizability of economic analyses of HIV ***:The available cost and cost-effectiveness evidence for EID of HIV,while not directly comparable across studies,covers a broad range of interventions and suggests most interventions designed to improve EID are cost

关键词： Cost effectiveness Diagnostics Low-and middle-income countries Point of care Early infant diagnosis Health systems

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High rate of complete histopathological response in hepatocellular carcinoma patients after combined transarterial chemoembolization and stereotactic body radiation therapy

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World Journal of Gastroenterology 2021年第24期27卷 3630-3642页

作者： Ulrike bauer Sabine Gerum Falk Roeder Stefan Münch Stephanie E Combs Alexander b Philipp Enrico N De Toni Martha M Kirstein Arndt Vogel Carolin Mogler bernhard Haller Jens Neumann Rickmer F braren Marcus R Makowski Philipp Paprottka Markus Guba Fabian geisler Roland M Schmid Andreas Umgelter Ursula Ehmer Internal Medicine Ⅱ Klinikum rechts der IsarTechnical University of MunichMunich 81675Germany Department of Radiotherapy and Radiation Oncology University of SalzburgSalzburg 5020Austria Department of Radiation Oncology University Hospital of MunichCampus GroßhadernLMU MunichMunich 81377Germany Department of Radiation Oncology Klinikum rechts der IsarTechnical University of MunichMunich 81675Germany Department of Medicine II Liver CentreUniversity HospitalLMU MunichMunich 81377Germany Department of Gastroenterology Hepatology and EndocrinologyHannover Medical SchoolHannover 30625Germany Institute of Pathology Technical University of MunichMunich 81675Germany Institute of Medical Informatics Statistics and EpidemiologyKlinikum rechts der IsarTechnical University of MunichMunich 81675Germany Institute of Pathology Faculty of MedicineUniversity Hospital of MunichMunich 81377Germany Institute of Diagnostic and Interventional Radiology Klinikum rechts der IsarTechnical University of MunichMunich 81675Germany Institute of Diagnostic and Interventional Radiology Section for Interventional RadiologyKlinikum rechts der IsarTechnical University of MunichMunich 81675Germany Department of General- Visceral-Vascular-and Transplant-SurgeryUniversity hospital of MunichCampus GroßhadernLMU MunichMunich 81377Germany Emergency Department Vivantes hospital groupHumboldt hospitalBerlin 13509Germany

bACKGROUND Liver transplantation(LT)presents a curative treatment option in patients with early stage hepatocellular carcinoma(HCC)who are not eligible for resection or ablation *** to a risk of up 30%for waitlist drop-out upon tumor progression,bridging therapies are used to halt tumor *** chemoembolization(TACE)and less commonly stereotactic body radiation therapy(SbRT)or a combination of TACE and SbRT,are used as bridging therapies in ***,it remains unclear if one of those treatment options is *** analysis of explant livers after transplantation provides the unique opportunity to investigate treatment response by *** To analyze histopathological response to a combination of TACE and SbRT in HCC in comparison to TACE or SbRT *** In this multicenter retrospective study,27 patients who received liver transplantation for HCC were *** received either TACE or SbRT alone,or a combination of TACE and SbRT as bridging therapy to liver *** explants of all patients who received at least one TACE and/or SbRT were analyzed for the presence of residual vital tumor tissue by histopathology to assess differences in treatment response to bridging *** analysis was performed using Fisher-Freeman-Halton exact test,Kruskal-Wallis and Mann-Whitney-U *** Fourteen patients received TACE only,four patients SbRT only,and nine patients a combination therapy of TACE and *** were no significant differences between groups regarding age,sex,etiology of underlying liver disease or number and size of tumor ***,analysis of liver explants revealed that almost all patients in the TACE and SbRT combination group(8/9,89%)showed no residual vital tumor tissue by histopathology,whereas TACE or SbRT alone resulted in significantly lower rates of complete histopathological response(0/14,0%and 1/4,25%,respectively,P value<0.001).CONCLUSION Our data suggests th

关键词： Hepatocellular carcinoma Transarterial chemoembolization Stereotactic body radiation therapy bridging therapy Liver transplantation

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WOX5-IAA17 feedback circuit mediated cellular auxin response is crucial for Arabidopsis root patterning

WOX5-IAA17 feedback circuit mediated cellular auxin response...

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从植物科学到农业发展——2012全国植物生物学大会

作者： Krzysztof Wabnik Stephan Pollmann Steffen Vanneste Willy Govaerts Jakub Rolcik Markus geisler Jiri Friml Department of Plant Systems biology VIB and Department of Plant Biotechnology and GeneticsGhent UniversityB-9052 GentBelgium Ruhr-Universitt bochum Lehrstuhl für Pflanzenphysiologie44801 Bochum Germany Department of Applied Mathematics and Computer Science Ghent University9000 GentBelgium Laboratory of Growth Regulators Centre of the Region Hana for Biotechnological and Agricultural Research and Faculty of SciencePalacky University78371 OlomoucCzech Republic Department of biology Plant BiologyUniversity of Fribourg1700 FribourgSwitzerland

In plants,the patterning of root meristem requires a gradient-guided auxin maximum that depends on the concerted action of polar auxin transport,auxin biosnythesis and intracellular auxin ***,mechanisms underlying this auxin gradient dependent root patterning are not fully ***,we present unexpected evidence that the activity of WUSCHEL-RELATED HOMEObOX 5(WOX5) transcription factor modulates free auxin production in the quiescent center(QC) of the root and thus assures the maintenance of auxin maximum in the root ***,WOX5 expression is inhibited in a feedback-dependent manner by canonical auxin signaling that involves indole-3-acetic acid 17(IAA17) auxin response ***,we used loss-of-function and gain-of-function mutant analysis complemented by computer simulation study to identify and test the novel feedback mechanism that links WOX5-dependent auxin production to IAA17-mediated cellular auxin *** findings demonstrate that this feedback circuit is essential for the maintenance of auxin gradient in the root tip and the auxin-mediated root distal stem cell(DSC) differentiation.

关键词： WOX5 auxin IAA17/AXR3 root patterning computer simulation.

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